Expansion reamer



R. JOHNSON ET AL EXBANsIoN REAMER Filed may 15, 192?.

Patented 0d. 21, 1924i.

nuire' stares isiizs'eg sereni' since.

ROBERT JOHNSON AND iii/innen Mon-EAU, or NDW BEDFORD, iviassAoHusE'rrs.

EXPANSION BEAMER.

Application led May 15,

To all idiom t 'may cof/wcm:

Be it known that we, ROBERT JOHNSON and AMEDEE MOREAU, citizens of the United States, residing at lYew Bedford, in the county of Bristol and State of Massachusetts, have invented'certain new and usefulY Improvements in an Expansion Beamer; and we do declare the following to be a full, olea-r, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an improved expansion reamer, and it has for its principal object to generally improve upon devices of this class by providingone of cxtreme simplicity and durability which is such in construction as to permit accurate and line adjustment of the cutting blades.

More specifically, it is another object of the invention to produce a reainer ofV the above type wherein the blades are moved outwardly by novel means against the action of the spring lingers of a unique device mountedL on the body, these fingers co-acting with the oppositeends of the blades.

Other objects and Yadvantages of the invention will be apparent during the course of the follo-wing description.

in the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same: n

Figure l is an elevational view of a f reamer constructed in accordance with this invention.

Figure 2 is a central longitudinal sectional view thereof.

Figure 3 is a transverse sectiontaken on 'the line 3-3 of Figures l and 2.

' Figures 4 and 5 are detail elevations of the expander and cutting blade respectively.

in the drawings, the numeral l represents an elongated cylindrical body which is provided with a bore 2 opening through one end, the same being formed with internal screw-tliieads at its open end as shown. yThis body is also provided with a plurality of elongated circumferentially spaced slots 3 which communicate with the bore, there being a plurality of flat elongated cutting-blades 4 arranged in these slots and having their inner edges extend- Y ing into the bore. As clearly seen in l? igures 2 and 5, the cutting-bladesxhave their 1922. Serial No. 561,243.

there is no liability of the expander being accidently withdrawn from the bore in the body. l/Vhile on thisexpander, it may be well to state that it is equipped at its outer vend with a screwthreaded portion 8 which co-acts with the threads at the outerwopen y end of the aforesaid bore, together with a stop flange 9 and aflat faced wrench-engaging. portion 10. By referring again to the cutting-blades, 4 it will be seen that these are equipped at their opposite ends with notches ll with which .the free ends of the spring lingers l2' of the removable collars 13 co-act. It is the normal tendency of these fingers 'to exert an inward pressure on the cutting-blades. However, the lingersv are sufficiently resilient to permit full adjustment of the blades. The collars 13V are held in place by small set-screwsl4 so as to permit them to be removed whenever necessary to permit removal of the blades for sharpening. We are led to state here that in actual practice, the outer edges' of the blades will be beveled from one flatface to the opposite face to produce an extremely fine cutting edge. However, it is understood that they may be sharpened otherwise as it does not in any way affect the features of the invention. Y

Assuming that it is desired to radially expand the cutting-blades fromthe contracted position shown in Figure 2, it is obvious that by simply applying a wrench or the like to the part l0 of the expander and rotating the latter to move it inwardly in the bore of the body, the conical parts 6 will act against the inclined surfaces of the cutting-blades to move them outwardly fingers exert an inward pressure on the V blades and automatically force them in-Y- wardly. i

Although it is not essen'tial, it is understood that in actual practice, the body l Vmay be formed between the cutting-blades with elongated grooves 15 to serve as pockets for collecting the shavings and to insure unretarded rotation of the reamer when in use.

By carefully considering the description in connection with the drawings, persons familiar with device of this class will doubtless be able to obtain a clear understanding of the invention. Therefore, a more lengthy and detailed description is deemed unnecessary. l

Since probably the best results may be obtained with the construction and arrangement herein shown and described, this is taken `as the preferred embodiment of the invention. However, we wish it to be understood that minor changes in coming within the scope of the invention as claimed may be resorted to if desired.

l/Ve cla-im:

l. An expansion reamer comprising a body provided with a central longitudinal bore and circumferentially spaced elongated slots communicating with said bore, blades arranged in said slots and having their inner ends extending into the bore, an expander cooperative with the blades for expanding them, collars removably iltted on the body and embodying circumferentially spaced spring-lingers eO-operative with the opposite ends of the blades for automatically moving them inward as the expander is withdrawn from the bore.

2. An expansion reamer comprising a substantially cylindrical body formed with a longitudinal bore opening` through one end and provided at this end with screw-threads, said body being provided with a plurality of circumferentially spaced elongated sloits opening into said bore and terminating in spaced relation from the opposite ends of the body, a plurality of blades arranged in said slots, said blades being formed on their inner longitudinal edges with spaced shoulders connected by inclined surfaces, said blades being also notched at their outer ends, an expanderl arranged in the bore and' having its screw-threaded part engaged with the screw-threads in the latter, being also equipped with a stop-flange, a wrench-engaging portion, and spaced conical parts c0- operative with the inclined surfaces of said lades and collars arranged on said body, one at the outer end and one intermediate the. ends, said collars being equipped with circumferentially spaced spring-fingers cooperative with the notched ends of said blades for exerting an inward pressure on the latter.

3. nu ex iansible rea-mer comprising a body having a plurality of recesses, blades seated therein, each blade having eXtensions at its ends forming shoulders, means for causing the blades to move radially and collars nicunted on the body and having spring lingers extending therefrom and engaging the shoulders at the ends of the blades for retaining #the blades in the recesses.

ln testimony whereof we have hereunto set our hands.

ROBERT JOHNSON. AMEDEE MOREAU. 

